updated node modules

nodejs/node_modules/stylus/lib/nodes/node.js

@@ -174,7 +174,7 @@ Node.prototype = {
   operate: function(op, right){
     switch (op) {
       case 'is a':
-        if ('string' == right.nodeName) {
+        if ('string' == right.first.nodeName) {
           return nodes.Boolean(this.nodeName == right.val);
         } else {
           throw new Error('"is a" expects a string, got ' + right.toString());